From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [PATCH v2 hmm 08/11] mm/hmm: Remove racy protection against double-unregistration Date: Fri, 7 Jun 2019 10:57:53 -0300 Message-ID: <20190607135753.GH14802@ziepe.ca> References: <20190606184438.31646-1-jgg@ziepe.ca> <20190606184438.31646-9-jgg@ziepe.ca> <88400de9-e1ae-509b-718f-c6b0f726b14c@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Disposition: inline In-Reply-To: <88400de9-e1ae-509b-718f-c6b0f726b14c-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: amd-gfx-bounces-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org Sender: "amd-gfx" To: John Hubbard Cc: Andrea Arcangeli , Ralph Campbell , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Felix.Kuehling-5C7GfCeVMHo@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, Jerome Glisse , amd-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org List-Id: dri-devel@lists.freedesktop.org T24gVGh1LCBKdW4gMDYsIDIwMTkgYXQgMDg6Mjk6MTBQTSAtMDcwMCwgSm9obiBIdWJiYXJkIHdy b3RlOgo+IE9uIDYvNi8xOSAxMTo0NCBBTSwgSmFzb24gR3VudGhvcnBlIHdyb3RlOgo+ID4gRnJv bTogSmFzb24gR3VudGhvcnBlIDxqZ2dAbWVsbGFub3guY29tPgo+ID4gCj4gPiBObyBvdGhlciBy ZWdpc3Rlci91bnJlZ2lzdGVyIGtlcm5lbCBBUEkgYXR0ZW1wdHMgdG8gcHJvdmlkZSB0aGlzIGtp bmQgb2YKPiA+IHByb3RlY3Rpb24gYXMgaXQgaXMgaW5oZXJlbnRseSByYWN5LCBzbyBqdXN0IGRy b3AgaXQuCj4gPiAKPiA+IENhbGxlcnMgc2hvdWxkIHByb3ZpZGUgdGhlaXIgb3duIHByb3RlY3Rp b24sIGl0IGFwcGVhcnMgbm91dmVhdSBhbHJlYWR5Cj4gPiBkb2VzLCBidXQganVzdCBpbiBjYXNl IGRyb3AgYSBkZWJ1Z2dpbmcgUE9JU09OLgo+ID4gCj4gPiBTaWduZWQtb2ZmLWJ5OiBKYXNvbiBH dW50aG9ycGUgPGpnZ0BtZWxsYW5veC5jb20+Cj4gPiBSZXZpZXdlZC1ieTogSsOpcsO0bWUgR2xp c3NlIDxqZ2xpc3NlQHJlZGhhdC5jb20+Cj4gPiAgbW0vaG1tLmMgfCA5ICsrLS0tLS0tLQo+ID4g IDEgZmlsZSBjaGFuZ2VkLCAyIGluc2VydGlvbnMoKyksIDcgZGVsZXRpb25zKC0pCj4gPiAKPiA+ IGRpZmYgLS1naXQgYS9tbS9obW0uYyBiL21tL2htbS5jCj4gPiBpbmRleCBjNzAyY2Q3MjY1MWI1 My4uNjgwMmRlNzA4MGQxNzIgMTAwNjQ0Cj4gPiArKysgYi9tbS9obW0uYwo+ID4gQEAgLTI4NCwx OCArMjg0LDEzIEBAIEVYUE9SVF9TWU1CT0woaG1tX21pcnJvcl9yZWdpc3Rlcik7Cj4gPiAgICov Cj4gPiAgdm9pZCBobW1fbWlycm9yX3VucmVnaXN0ZXIoc3RydWN0IGhtbV9taXJyb3IgKm1pcnJv cikKPiA+ICB7Cj4gPiAtCXN0cnVjdCBobW0gKmhtbSA9IFJFQURfT05DRShtaXJyb3ItPmhtbSk7 Cj4gPiAtCj4gPiAtCWlmIChobW0gPT0gTlVMTCkKPiA+IC0JCXJldHVybjsKPiA+ICsJc3RydWN0 IGhtbSAqaG1tID0gbWlycm9yLT5obW07Cj4gPiAgCj4gPiAgCWRvd25fd3JpdGUoJmhtbS0+bWly cm9yc19zZW0pOwo+ID4gIAlsaXN0X2RlbF9pbml0KCZtaXJyb3ItPmxpc3QpOwo+ID4gLQkvKiBU byBwcm90ZWN0IHVzIGFnYWluc3QgZG91YmxlIHVucmVnaXN0ZXIgLi4uICovCj4gPiAtCW1pcnJv ci0+aG1tID0gTlVMTDsKPiA+ICAJdXBfd3JpdGUoJmhtbS0+bWlycm9yc19zZW0pOwo+ID4gLQo+ ID4gIAlobW1fcHV0KGhtbSk7Cj4gPiArCW1lbXNldCgmbWlycm9yLT5obW0sIFBPSVNPTl9JTlVT RSwgc2l6ZW9mKG1pcnJvci0+aG1tKSk7Cj4gCj4gSSBoYWRuJ3QgdGhvdWdodCBvZiBQT0lTT05f KiBmb3IgdGhlc2UgdHlwZXMgb2YgY2FzZXMsIGl0J3MgYSAKPiBnb29kIHRlY2huaXF1ZSB0byBy ZW1lbWJlci4KPiAKPiBJIG5vdGljZWQgdGhhdCB0aGlzIGlzIG5vdyBkb25lIG91dHNpZGUgb2Yg dGhlIGxvY2ssIGJ1dCB0aGF0Cj4gZm9sbG93cyBkaXJlY3RseSBmcm9tIHlvdXIgY29tbWl0IGRl c2NyaXB0aW9uLCBzbyB0aGF0IGFsbCBsb29rcyAKPiBjb3JyZWN0LgoKWWVzLCB0aGUgdGhpbmcg YWJvdXQgUE9JU09OIGlzIHRoYXQgaWYgeW91IGV2ZXIgcmVhZCBpdCB0aGVuIHlvdSBoYXZlCmZv dW5kIGEgdXNlIGFmdGVyIGZyZWUgYnVnIC0gdGh1cyB3ZSBzaG91bGQgbmV2ZXIgbmVlZCB0byB3 cml0ZSBpdAp1bmRlciBhIGxvY2sgKGp1c3QgYWZ0ZXIgYSBzZXJpYWxpemluZyBsb2NrKQoKTm9y bWFsbHkgSSB3b3VsZG4ndCBib3RoZXIgYXMga2ZyZWUgZG9lcyBwb2lzb24gYXMgd2VsbCwgYnV0 IHNpbmNlIHdlCmNhbid0IGVhc2lseSBhdWRpdCB0aGUgcGF0Y2hlcyB5ZXQgdG8gYmUgc3VibWl0 dGVkIHRoaXMgc2VlbXMgc2FmZXIKYW5kIHdpbGwgcmVsaWFibHkgY2F1c2UgdGhvc2UgcGF0Y2hl cyB0byBleHBsb2RlIHdpdGggYW4gb29wcyBpbgp0ZXN0aW5nLgoKVGhhbmtzLApKYXNvbgpfX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fXwphbWQtZ2Z4IG1haWxp bmcgbGlzdAphbWQtZ2Z4QGxpc3RzLmZyZWVkZXNrdG9wLm9yZwpodHRwczovL2xpc3RzLmZyZWVk ZXNrdG9wLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2FtZC1nZng=